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2. An Intense Out-of-Season Rebound of Influenza Activity After the Relaxation of Coronavirus Disease 2019 Restrictions in Beijing, China.

Author

Zhang, Li, Duan, Wei, Ma, Chunna, Zhang, Jiaojiao, Sun, Ying, Ma, Jiaxin, Wang, Yingying, Zhang, Daitao, Wang, Quanyi, Liu, Jue, and Liu, Min

Subjects
COVID-19, INFLUENZA, COVID-19 pandemic, H7N9 Influenza, CORONAVIRUS diseases
Abstract

Background The aim of this study was to investigate the changes of epidemic characteristics of influenza activity pre– and post–coronavirus disease 2019 (COVID-19) in Beijing, China. Methods Epidemiologic data were collected from the influenza surveillance system in Beijing. We compared epidemic intensity, epidemic onset and duration, and influenza transmissibility during the 2022–2023 season with pre-COVID-19 seasons from 2014 to 2020. Results The overall incidence rate of influenza in the 2022–2023 season was significantly higher than that of the pre-COVID-19 period, with the record-high level of epidemic intensity in Beijing. The onset and duration of the influenza epidemic period in 2022–2023 season was notably later and shorter than that of the 2014–2020 seasons. Maximum daily instantaneous reproduction number (Rt) of the 2022–2023 season (Rt = 2.31) was much higher than that of the pre-COVID-19 period (Rt = 1.49). The incidence of influenza A(H1N1) and A(H3N2) were the highest among children aged 0–4 years and 5–14 years, respectively, in the 2022–2023 season. Conclusions A late, intense, and short-term peak influenza activity was observed in the 2022–2023 season in Beijing. Children <15 years old were impacted the most by the interruption of influenza circulation during the COVID-19 pandemic. Maintaining continuous surveillance and developing targeted public health strategies of influenza is necessary. [ABSTRACT FROM AUTHOR]

Published
2024
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3. The role of absolute humidity in influenza transmission in Beijing, China: risk assessment and attributable fraction identification.

Author

Zhang, Li, Ma, Chunna, Duan, Wei, Yuan, Jie, Wu, Shuangsheng, Sun, Ying, Zhang, Jiaojiao, Liu, Jue, Wang, Quanyi, and Liu, Min

Subjects
*HUMIDITY, *RISK assessment, *SEASONAL influenza, *DESCRIPTIVE statistics, *INFLUENZA, *ETIOLOGIC fraction, *INFECTIOUS disease transmission
Abstract

To assess the impact of absolute humidity on influenza transmission in Beijing from 2014 to 2019, we estimated the influenza transmissibility via the instantaneous reproduction number (Rt), and evaluated its nonlinear exposure-response association and delayed effects with absolute humidity by using the distributed lag nonlinear model (DLNM). Attributable fraction (AF) of Rt due to absolute humidity was calculated. The result showed a significant M-shaped relationship between Rt and absolute humidity. Compared with the effect of high absolute humidity, the low absolute humidity effect was more immediate with the most significant effect observed at lag 6 days. AFs were relatively high for the group aged 15–24 years, and was the lowest for the group aged 0–4 years with low absolute humidity. Therefore, we concluded that the component attributed to the low absolute humidity effect is greater. Young and middle-aged people are more sensitive to low absolute humidity than children and elderly. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Surveillance for avian influenza A(H7N9), Beijing, China, 2013

Author

Yang, Peng, Pang, Xinghuo, Deng, Ying, Ma., Chunna, Zhang, Daitao, Sun, Ying, Shi, Weixian, Lu, Guilan, Zhao, Jiachen, Liu, Yimeng, Peng, Xiaomin, Tian, Yi, Qian, Haikun, Chen, Lijuan, and Wang, Quanyi

Subjects
Avian influenza -- Distribution -- Prevention -- Diagnosis, Infection control -- Methods, Company distribution practices, Health
Abstract

On March 31, 2013, three human infections with a novel avian influenza A(H7N9) virus were identified in Shanghai and Anhui Provinces in southeastern China (1,2). As of June 30, 2013, [...]

Published
2013
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13. Role of presymptomatic transmission of COVID-19: evidence from Beijing, China

Author

Zhang, Yi, primary, Muscatello, David, additional, Tian, Yi, additional, Chen, Yanwei, additional, Li, Shuang, additional, Duan, Wei, additional, Ma, Chunna, additional, Sun, Ying, additional, Wu, Shuangsheng, additional, Ge, Lin, additional, Yang, Peng, additional, Jia, Lei, additional, Wang, Quanyi, additional, and MacIntyre, Chandini Raina, additional

Published
2020
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15. Avian influenza A (H9N2) virus infections among poultry workers, swine workers, and the general population in Beijing, China, 2013‐2016: A serological cohort study

Author

Ma, Chunna, primary, Cui, Shujuan, additional, Sun, Ying, additional, Zhao, Jiachen, additional, Zhang, Daitao, additional, Zhang, Li, additional, Zhang, Yi, additional, Pan, Yang, additional, Wu, Shuangsheng, additional, Duan, Wei, additional, Zhang, Man, additional, Yang, Peng, additional, and Wang, Quanyi, additional

Published
2019
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16. Influenza vaccine effectiveness in preventing laboratory-confirmed influenza in outpatient settings: A test-negative case-control study in Beijing, China, 2016/17 season

Author

Wu, Shuangsheng, primary, Pan, Yang, additional, Zhang, Xinxin, additional, Zhang, Li, additional, Duan, Wei, additional, Ma, Chunna, additional, Zhang, Yi, additional, Zhang, Man, additional, Sun, Ying, additional, Yang, Peng, additional, Wang, Quanyi, additional, and Ma, Jun, additional

Published
2018
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17. Moderate influenza vaccine effectiveness against influenza A(H1N1)pdm09 virus and low effectiveness against A(H3N2) virus among older adults during 2013–2014 influenza season in Beijing, China

Author

Zhang, Li, primary, Pan, Yang, additional, Ma, Chunna, additional, Duan, Wei, additional, Sun, Ying, additional, Wu, Shuangsheng, additional, Zhang, Man, additional, Tian, Yi, additional, Zheng, Yang, additional, Yang, Peng, additional, and Wang, Quanyi, additional

Published
2018
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18. Infectious Disease-Specific Health Literacy Survey

Author

Yang, Peng, primary, Dunzhu, Ciren, additional, Widdowson, Marc-Alain, additional, Wu, Shuangsheng, additional, Ciren, Pengcuo, additional, Duoji, Dunzhu, additional, Pingcuo, Wangqing, additional, Dun, Bian, additional, Ma, Chunna, additional, Li, Jie, additional, Pang, Xinghuo, additional, and Wang, Quanyi, additional

Published
2018
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20. Role of presymptomatic transmission of COVID-19: evidence from Beijing, China

Author

Zhang, Yi, Muscatello, David, Tian, Yi, Chen, Yanwei, Li, Shuang, Duan, Wei, Ma, Chunna, Sun, Ying, Wu, Shuangsheng, Ge, Lin, Yang, Peng, Jia, Lei, Wang, Quanyi, and MacIntyre, Chandini Raina

Abstract

BackgroundThe presymptomatic transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been documented in limited clusters, and it is predicted through modelling. However, there is a lack of evidence from observations with a large sample size.MethodsWe used data from meticulous contact tracing of people exposed to cases of SARS-CoV-2 to estimate the proportion of cases that result from the presymptomatic transmission of the virus in Beijing during January 2020 and February 2020.ResultsThe results showed that presymptomatic transmission occurred in at least 15% of 100 secondary COVID-19 cases. The earliest presymptomatic contact event occurred 5 days prior to the index case’s onset of symptoms, and this occurred in two clusters.ConclusionsThe finding suggested that the contact tracing period should be earlier and highlighted the importance of preventing transmission opportunities well before the onset of symptoms.

Published
2021
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23. Infectious disease-specific health literacy in Tibet, China

Author

Yang, Peng, primary, Dunzhu, Ciren, additional, Widdowson, Marc-Alain, additional, Wu, Shuangsheng, additional, Ciren, Pengcuo, additional, Duoji, Dunzhu, additional, Pingcuo, Wangqing, additional, Dun, Bian, additional, Ma, Chunna, additional, Li, Jie, additional, Pang, Xinghuo, additional, and Wang, Quanyi, additional

Published
2016
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33. Estimated burden of group a streptococcal pharyngitis among children in Beijing, China.

Author

Shuangsheng Wu, Xiaomin Peng, Zuyao Yang, Chunna Ma, Daitao Zhang, Quanyi Wang, Peng Yang, Wu, Shuangsheng, Peng, Xiaomin, Yang, Zuyao, Ma, Chunna, Zhang, Daitao, Wang, Quanyi, and Yang, Peng

Subjects
PHARYNGITIS, STREPTOCOCCUS, BURDEN of care, INFLAMMATION, COMMUNICABLE disease treatment, STREPTOCOCCAL disease diagnosis, STREPTOCOCCAL diseases, DISEASE incidence
Abstract

Background: Burden of Group A streptococcus (GAS) pharyngitis is scarce in developing countries, still unknown in China. The objective of this study was to determine the incidence of clinical cases of pharyngitis and GAS culture-positive pharyngitis, and their outpatient visits among children aged 0-14 years in Beijing, the capital of China.Methods: Multiplier model was used to estimate the numbers of pharyngitis cases, based on reported numbers of clinical cases and GAS culture-positive rates from GAS surveillances in Beijing, consultation rate, population coverage of GAS surveillances, sampling success rate, and test sensitivity of GAS culture from previous studies, surveys and surveillances.Results: An average of 29804.6 (95 % CI: 28333.2-31276.0) clinical cases of pharyngitis per 100,000 person-years occurred among children aged 0-14 years, resulting in correspondingly 19519.0 (95 % CI: 18516.7-20521.2) outpatient visits per 100,000 person-years from 2012 to 2014 in Beijing. On average, there were 2685.1 (95 % CI: 2039.6-3330.6) GAS culture-positive cases of pharyngitis and 1652.7 (95 % CI: 1256.5-2049.0) outpatient visits per 100,000 person-years during the same period. The estimated burden of GAS pharyngitis was significantly higher than that of scarlet fever. Children aged 5-14 years had a higher burden of GAS pharyngitis than those aged 0-4 years.Conclusions: The present data suggests that GAS pharyngitis is very common in children in China. Further studies and surveillances are needed to monitor trends and the effectiveness of control measures. [ABSTRACT FROM AUTHOR]

Published
2016
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34. A Serological Survey of Antibodies to H5, H7 and H9 Avian Influenza Viruses amongst the Duck-Related Workers in Beijing, China

Author

Yang, Peng, primary, Ma, Chunna, additional, Shi, Weixian, additional, Cui, Shujuan, additional, Lu, Guilan, additional, Peng, Xiaomin, additional, Zhang, Daitao, additional, Liu, Yimeng, additional, Liang, Huijie, additional, Zhang, Yi, additional, Zhang, Li, additional, Seale, Holly, additional, and Wang, Quanyi, additional

Published
2012
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35. H7N9 not only endanger human health but also hit stock marketing.

Author

Jiang Y, Zhang Y, Ma C, Wang Q, Xu C, Donovan C, Ali G, Xu T, and Sun W

Abstract

Objective: This study aims to discuss the correlation between daily reported H7N9 cases and stock price indices in China., Methods: Information on daily reported H7N9 cases and stock market sectors indices between February 19, 2013 and March 31, 2014 were collected. A distributed lag non-linear model was used to describe the variation trend for the stock indices., Results: The daily reported number of H7N9 cases was associated with the closing price of the Avian Influenza Sector Index (P < 0.05) and the opening price of the Shanghai Composite Index (P = 0.029). The Avian Influenza Sector Index decreased with increasing of daily reported case number when daily reported cases ≤ 4. Case number was associated with the opening/closing price of the Chinese Traditional Medicine Sector Index, the Biological Product Sector Index, and the Biomedicine Sector Index (P < 0.05)., Conclusion: New or reemerging infectious diseases epidemic cause economic loss which is reflected in movements in stock prices., Competing Interests: DECLARATIONS Conflict of interests We declare that there is no conflict of interest.

Published
2017
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